Do we really know the truth?

Can we rely on the media to provide us the truth behind every news coverage? As much as i used to think the media is the source of truth, now i begin to doubt so. There are occassions when we begin to question, is the media really providing us with the correct informations? Is the news we read everyday merely based on bias judgements, popularity, or whether it will help the media company to gain profit? How can we possibly trust something that we have doubts about?
Even countries like America cannot provide its people with the every details of truth despite being greatly known as a country that pratices freedom of press, what more for other non-liberal countries or countries that proclaim themselves as democratic, but in fact practises the opposite.Maybe in some way or another, such truths are said to be kept from public so as to prevent the people to reform against the government. But what can we say when Sinclair Broadcasting refused to televise a segment of ABC’s “Nightline,” where the names of those killed in Iraq were read? Why cant the public be told about this fact? How would this pose a threat to the government?
In some other cases where some opinions or comments which were thought to be "harmful" were deliberately censored off, not giving it a chance to be revealed publicly. Is this what we, as a democraticsociety should be practicing? Some what, i strongly feel that the public should be given the full overview and judge for themselves base on the truth and not by the vague picture the media had beautifully painted.